Master clamping device for duplicators



' Nov. 17, 1936. F. w. STORCK 2,061,525

MASTER CLAMPING DEVICE FOR DUPLICATORS v ""iled March 25, 1935 2 Sheets-Sheet l m 2? "*'7+5- 1:: 2c] 11; 50 INVENTOR. lldmok w 2812104:

ATTORNEY.

Patented N v. 17, 1936 ,Mss'ma 01mins DEVICE FOR DUPLIOATOBS Frederick w. Storck', Arlington, Mass., assignor to Standard Malling Machines Company,

Everett, Mass, a corporation of Massachusetts Application March 22, 1935, Serial No. 12,602

' 11 Claims. (Cl. 101-. 132) This invention relates to duplicating machines wherein therecord copy or master sheet is made in reverse with suitable copying ink and reproduced therefrom on sheets of paper, or the like,

5 having a moistened face and my present invention relates more particularly toa clamp for Quickly and conveniently securing one edge of the master to the printing platen of a duplicating machine.

1 -Heretofore it has been the general practice to i provide a rotary type duplicating machine with a master sheet clamp member withopposed clamping fac, s substantially-parallel to the medial radius the platen. This construction effects a crease in the clamp end of the sheet as it causes the portion thus clamped to be disposed at a substantially right angle to the sheet as the drum is rotated in its printing operation.

This effect is a disadvantage when it is neces- 20 sary to file the master sheets for further use and while this effect is not excessive in the use of a relatively thin master sheet, it will practically ruin the value of a master record formed on a heavier or record card-like material, as these cards, after use, will not properly stack, due to their bent end, in a limited formation in. a file drawer without the necessity of flexing the bent portion back to its original plane.

Therefore, one of the objects in my present invention is to provide a master clamp for a rotary duplicating machine that will effectively clamp the edge of the sheet with a minimum amount of distortion so asto permit continued use and convenient filing of the masters.

Another object in my invention is to provide a clamping device whereby the master may be quickly and easily positioned for clamping and i in proper alignment for registration with clear sheets to be printed upon.

A further object of my invention is to provide a novel and effective clamp actuating means that may 'be embodied within the rotary printing platen/of the machine. and operated by a simple unobstructive external means.

45 My objects further contemplate a novel structure which eliminates the usual external pivots, tensioning means and levers and which permits the clamp, when in operative position, to lie flush with the face/of the printing platen.

50 With the above and other objects in view, my invention comprises a novel combination and arrangement of parts hereinafter described and p more specifically. pointed out' in the appended claims. 55 In the accompanying drawings I have shown my invention embodied with a rotary duplicating machine, of a type fully shown and described in my United States Letters Patent No. 1,964,933,

issued July 3, 1934, suflicient to enable those skilled in the art to understand the construction 5 and operation thereof.

Referring to the drawings:- Fig. 1 is a vertical section through a rotary type duplicator having my master clamping device embodied therewith. I

Fig. 2 is a transverse section taken substantially along line 22, Fig. 1 with the printing platen rotated 90 in the direction of the arrow.

Fig. 3 is a detached transverse section of my clamping device in its closed operative position.

Fig. 4 is a view corresponding to Fig. 3, but shows the clamping device in" its open position.

Fig. 5 is a longitudinal sectional view taken substantially along line 5-5, Fig. 6.

Fig. 6 is a modification of my clamping device as shown at Fig. 3.

Fig. 'l is a longitudinal sectional view taken 1 substantially along line l-I, Fig. 6.

The duplicating mwchine The rotary type duplicatlngmachine shown in the drawings is provided with opposed side frames iii, in which are mounted the operating elements of the duplicator. These opposed side frames it are retained in spaced relation by suitable tie rods 30 ll, l2, l3 and ll. The printing platen I5 is rotatably mounted on the shaft l6 which, in turn, is secured against rotation in the side frames.

The printing platen .l5 is intermittently rotated by drive mechanism which comprises a pinion i1 5 which may be rotated by any suitable source of I power. This pinion l1 meshes with and rotates an intermediate gear l8 to which the intermittent gear I9 is secured; the-intermittent gear [9, in turn, mehhes with a coacting intermittent gear 20 which is adiustably secured to the printing platen i5. 7

In operation, the gear I 8 is rotated in a contraclockwise direction which causes the printing platen ii to be rotated in a clockwise direction, as indicated by the arrows. The construction and function of the intermittent gears I8, 20 is well known in the art. 5

The clear sheet to be printed upon is fed to contact with moistening and feeding rolls II, 22. The feed roll 22 is provided with a shaft 23 which extends beyond each end thereof to form journals designed to rotate in suitable adjustable bearings in the side frames. The moistening roll ii is secured to a shaft 24 rotatably mounted in sultall gear 241) which is engaged by and rotated by an intermediate gear 240 which meshes with a gear 24d secured to the printing platen l 5. These feed and moistening rolls 2|, 22 are intermittently rotated with the printing platen l5.

As the clear sheet is advanced between the feed rolls 2|, 22 the under face, in this instance, is moistened by the moistening roll 21 which receives its moisture by means of capillary attraction of the wick 25 which is disposed in engagement with the moistening roll 2| and a fluid supbetween the rotating printing platen I5 and pressure roll l5d whereby the copy secured to the printing platen is reproduced on the moistened face of the clear sheet.

A rotary duplicating machine of the above general character isclearly shown and described in my Patents Nos. 1,964,933, issued July 3, 1934, and

1,988,056, issued January 15, 1935, therefore, fur-' ther detailed description is thought unnecessary.

The master sheet clamp is cut away to receive a clamp shoe 21 which extends between the opposed end walls of the platen. As illustrated, this clamp shoe 21 is secured to the opposed end walls of the platen by means of screws l5a threadedly engaged in'inwardly projecting portions l5b of the platen end walls. The outer portion of this clamp shoe 21 is provided with a, longitudinal rectangular recess 21a which forms shoulders 21b, 210 between the opposed outer faces 21d, 21e of said clamp shoe 21.

My outer clamp member 28 is formed with an outer arcuate face which, whenin closed engagement with the clamp shoe 21, effects a continuity of the peripheral face of the platen 15. This outer clamp member 28 is provided with a depending portion 28a adapted to engage in the clamp shoe recess 21a in a close but free relation. The depending portion 28a forms shoulders 28b, 280 for the opposed inner faces 28d, 28e of the outer clamp member 28.

v The outer clamp member 28 is provided with yielding tension means which, in this instance, comprise a plurality of inwardly extending studs 29 tfireadedly engaged in the outer clamp member 28 and projecting through suitable enlarged openings '21 in the clamp shoe 21. Each stud 29 is provided with an enlarged head 29a that acts as a bearing for one end of the compression spring 30 which encircles the stud 29. The opposed end of the compression spring 30 has its bearing against a washer 30a that encircles the stud 28 and has its bearing against the inner face of the clamp shoe 21.

Suitably supported within the clamp shoe 21 is a rotatable shaft 3| having an outer terminating the clamp member 28 compresses the springs 30.

As the clamp 28 is raised by the cam 32, the shoulder 282) will pivotally bear against its coacting 2,061,625 ble bearings, this shaft 24 has secured thereto a shoulder 21b and the longitudinal edge 28h of the clamp 28 will pivotally bear against the outer face of the clamp shoe 21.

The edge of the master sheet m to'be clamped is now positioned in the slot formed by the open faces 21e, 28c and against the stop formed by the clamp shoulder 290. The cam 32 is then rotated to its opposed position which permits the action of the springs '38 to close the clamp 28 tightly against the clamp shoe 21, thus engaging the edge of the master sheet m between the opposed clamping faces 21e, 28c, as shown at Fig. 3.

' At Figs. 6 and 7 I have shown a modification of my clamp shoe 21 wherein the clamp face 21h is provided with a'plurality of frictional inserts 33 which are slightly raised above the plane of this clamp face 21h. This modification shows one embodiment for the developing of additional friction between the master clamp faces, but it is obvious that various means may be employed for producing greater friction between the clamp faces and which I have contemplated, together with other modifications and arrangements within the scope of my invention and which would be obvious to those skilled in the art.

Having thus described my invention, what I claim is 1. A device of the character specified having a rotatable printing platen with means for rotating said platen, a master sheet clamping member normally disposed flush with the plane of the face of said platen with engaging means disposed within said platen and adapted to elevate one face of said clamp to form an aperture transversely of said platen face and at an angle of less than 90 to the tangency of the platen periphery.

2. A device of the character-specified having a revolvable printing platen with means for rotating saidplaten, clamping means adapted to clamp one edge of a master sheet to said printing platen, said last means comprising a removable shoe disposed in a recess of said platen and extending transversely of the platen face, a coacting clamping member for said shoe. with pressure means urging said member and shoe into engagement, said last member having an arcuate outer face normally forming a substantially continuous face plane for said platen, means to elevate one edge. of said last member to form a clamping slot between said clamping member and said shoe and transversely of said platen face, said clamping slot extending inwardly from the face of said platen at an angle of substantially less than 90 to the tangency of the platen periphery.

3. A device of the character specified having a revolvable printing platen with means for rotating said platen, means for clamping one edge of a master sheet to the printing platen, said last means comprising a removable shoe disposed in a recess of said platen and extending transversely of the platen face, a longitudinal recess forming opposed shoulders in the upper face of said shoe, a clamping member having a depending Por ion disposed between said shoulders and an outer arcuate face normally forming a substantially continuous face plane for said platen, pressure means for yieldingly retaining opposed faces of said shoe and clamp in normal close engagement with cam. actuating means adapted to engage said dependir? portion 'to elevate said clamping member to f rm a slot between opposed faces of said clamping member and shoe, said slot extending inwardly from the face of said platen to a stop formed by a shoulder of said depending portion, said slot being disposed at an angle of substantially less than 90 to the tangency of the platen periphery. 4. A device of thecharacter specified having a revolvable printing platen with means for rotating said platen, means for clamping one edge of said master sheet to the printing platen, said clamping means extending axially of the printing platen and having an outer face normally dis-- posed coincident to the face plane of said printing platen, guide members secured to said clamping means and extending inwardly into said platen, yielding means associated with said guide contact of the opposed axially extending edge by engagement of said last edge with said printing platen.

5. A duplicating machine as claimed in claim 4, having a cam element adapted to elevate, and releasably retain elevated, one axially extending edge of said clamping means.

6. A device of the character specified having a revolvable printing platenwith means for rotatting said platen, a clamping member extending axially of said printing platen and adapted to clamp one edge of a master sheet to said platen at an angle of substantially less than to the tangency of and below the periphery of said platen, said clamping member having an outer arcuate face which, when normally disposed, is flush with and forms a portion ofthe peripheral face of said platen with means for positioning said clamping member in opposed open and closed relation relative to said platen.

7. A clamping device as recited in claim 6 wherein rotative actuating means are provided for engaging and retaining said clamping member in an open relation relative to said platen.

8. A device of the character specified having a member in opposed open and closed relation relative to said platen, the outer face of said clamping member being disposed flush with, and forming a portion of, the peripheral face of said platen when said clamping member is in its closed position.

9. A clamping device as set forth in claim 8 wherein one of the opposed faces of said clamping member is provided with a resilient area projecting above said face.

10. A master sheet clamping device for a rotary duplicator platen comprising a clamping shoe adjacent the peripheral face of said platen with a yielding clamp bar having an arcuate outer face normally flush with the face of said platen and means for elevating one edge of said bar to form a clamp aperture extending transversely of said platen face and extending inwardly from the face of said platen at an angle of substantially less than 90 to the tangency of said platen face. 4

from said arcuate face at an angle of substantially less than 90 to the tangency of said arcuate face with rotative means adapted to engage said banand separate one edge thereof from the face plane of said shoe.

FREDERICK W. STORCK. 

